|Número de publicación||US5312446 A|
|Tipo de publicación||Concesión|
|Número de solicitud||US 07/935,953|
|Fecha de publicación||17 May 1994|
|Fecha de presentación||26 Ago 1992|
|Fecha de prioridad||26 Ago 1992|
|También publicado como||CA2120243A1, CA2120243C, DE69329526D1, DE69329526T2, EP0613390A1, EP0613390B1, WO1994005371A1|
|Número de publicación||07935953, 935953, US 5312446 A, US 5312446A, US-A-5312446, US5312446 A, US5312446A|
|Inventores||Jean M. Holschbach, Lucy M. Nichols, David L. Thompson|
|Cesionario original||Medtronic, Inc.|
|Exportar cita||BiBTeX, EndNote, RefMan|
|Citas de patentes (12), Otras citas (4), Citada por (211), Clasificaciones (11), Eventos legales (4)|
|Enlaces externos: USPTO, Cesión de USPTO, Espacenet|
This invention relates generally to the field of cardiac pacemakers, and more particularly relates to the compression and storage of analog signals therein.
A wide variety of cardiac pacemakers are known and commercially available. Pacemakers are generally characterized by which chambers of the heart they are capable of sensing, the chambers to which they deliver pacing stimuli, and their responses, if any, to sensed intrinsic electrical cardiac activity. Some pacemakers deliver pacing stimuli at fixed, regular intervals without regard to naturally occurring cardiac activity. More commonly, however, pacemakers sense electrical cardiac activity in one or both of the chambers of the heart, and inhibit or trigger delivery of pacing stimuli to the heart based on the occurrence and recognition of sensed intrinsic electrical events. A so-called "VVI" pacemaker, for example, senses electrical cardiac activity in the ventricle of the patient's heart, and delivers pacing stimuli to the ventricle only in the absence of electrical signals indicative of natural ventricular contractions. A "DDD" pacemaker, on the other hand, senses electrical signals in both the atrium and ventricle of the patient's heart, and delivers atrial pacing stimuli in the absence of signals indicative of natural atrial contractions, and ventricular pacing stimuli in the absence of signals indicative of natural ventricular contractions. The delivery of each pacing stimulus by a DDD pacemaker is synchronized with prior sensed or paced events.
Pacemakers are also known which respond to other types of physiological based signals, such as signals from sensors for measuring the pressure inside the patient's ventricle or measuring the level of the patient's physical activity. These are labeled "VVIR" for a single chamber version or "DDDR" for a dual chamber version.
The complexity of modern pacemakers, the occurrence of rare device failures, or, more commonly, physiologic changes, and device variables or drift dictate the need for numerous programmable parameters accessible noninvasively via an externally operated programmer. The need to assess system performance or troubleshoot the patient, device and/or lead system in an acute, clinical setting or long-term, while the patient is ambulatory, is increasing.
Ambulatory EKG monitoring is the most effective way of determining satisfactory pacemaker or cardioverter/defibrillator function. In the presence of a malfunction that has occurred or has been provoked by daily activity, there is no technique that provides better accuracy for determination of the state of the function of the implanted device and its interaction with the patient. Passive EKG monitoring with provocative testing, can frequently detect a malfunction of the implanted device and is the basic technique utilized today. Additionally, the storage of data in counters or, more recently, rate or trend histograms, and the use of telemetry markers to indicate device function may aid in the diagnosis of malfunction or may allow optimization of device performance. However, it is often impossible in an acute, clinical setting to duplicate specific daily events and activities, thus many problems are unresolved. Additionally, it is impossible to record for prolonged periods of time and even for short periods of time with adequate resolution. Lastly, event counters and histograms do not provide the temporal relationship between events to enable diagnosis of transiently occurring problems.
Episodic events such as transiently brief runs of pacemaker mediated tachycardia (PMT), supraventricular tachycardia (SVT) or syncope can be detected as a source of clinically significant symptoms by ambulatory monitoring and rarely occur during clinical passive EKG evaluation. Events related to daily activity, electromagnetic interference (EMI), loss of capture via specific body position or activity, and the effect of sleep or activity on patient/device interaction may be readily demonstrated by ambulatory monitoring.
However, ambulatory "holter" monitoring typically entails attaching tape-on electrodes to a patient and monitoring the surface EKG via a tape recorder or integrated circuit (IC) memory recorder worn on the patient's belt for a 24-hour period. This "strapped on" device causes patient discomfort and limits activity. If the transient event is not captured, the trial must be repeated or the troubleshooting process must be curtailed or changed to a trial and error method for problem resolution. Additionally, the evaluation of the 24 hours of stored data is a time intensive and expensive process. Lastly, standard holter monitoring has no capability for determining device function simultaneous with the stored EKG artifacts.
Devices have been proposed for the electronic storage and transmission of the analog information in an implantable medical device to solve the above listed problems and shortcomings. The most common method is to digitize (i.e. change to digital format) an analog signal for storage or transmission. For example, U.S. Pat. No. 4,223,678 by Langer, et al., discloses the recording of EGM data prior to and following the detection of an arrhythmic event and subsequentially delivered shock. Pre-event analog data is converted by an analog to digital converter (ADC) and stored in auxiliary memory while post-event data is stored in main memory. Both memories are frozen upon storing of the single episodic event.
U.S. Pat. No. 4,407,288 by Langer, et al., discloses a two micro-processor based implantable defibrillator with ECG recording capability. Pre-event detection data is stored via a low speed processor into memory via direct memory access (DMA). Upon event detection, the data for a single event is frozen.
U.S. Pat. No. 4,625,730 by Fountain, et al., discloses the storage of ECG data via DMA to memory. One event may be stored for a total time duration of 10.24 seconds. Also, the '730 patent discloses a hand-held patient programmer used as an actuator to trigger the storage of an event.
U.S. Pat. No. 4,295,474 by Fishell discloses the recording of ECGs as in the '678 patent along with the recording of time and number of arrhythmic episodes since the previous office visit. The ECG is converted by a six bit ADC at 50 Hz for the storage and memory of one event for a total duration of 80 seconds. Ten seconds of continuously stored data is contained in a section of memory to enable the freezing and storage of 10 seconds of pre-event data and 70 seconds of post-event data.
The prior art listed above may be typically characterized by digitizing data with an ADC, the storage of a single event with limited duration (10-80 seconds), no provision for extended storage times or storage of multiple events/episodes, generally low fidelity signals, and extended telemetry transmission times to external peripherals.
To obtain extended storage capability (long storage time or multiple storage of events), digitized analog signals, such as an ECG, would require very large memory storage capability--140 million bits of memory per day--(see Chapter 1, Part 4 "The Third Decade of Cardiac Pacing"). Memory of that size would require a large number of integrated circuits and would not fit in a typically sized implantable pulse generator, would cause excessive current drain from the battery during operation and require nearly five hours to uplink to a peripheral utilizing a "state-of-the-art" telemetry system. Proposed solutions to the large amount of memory required include data reduction techniques such as blanking out all signals except for the signals indicative of the atrial and ventricular depolarization and repolarization (PQRST interval) which is then converted via standard techniques. This results in a reduction of the storage requirements of only approximately 50 percent. Additionally, compression techniques such as Coordinate-Reduction-Time-Encoding-System (CORTES) or Amplitude-Zone-Epoch-Time-Coding (AZTEC) may be used to achieve up to 10:1 data compression (see Data Compression--Techniques and Applications, Pg. 256-259, T. J. Lynch). However these techniques are not suitable for use in implantable medical devices because of the extensive processing power required to compress and store data real time.
Additionally, data stored in an implantable medical device's volatile memory can be erased or contaminated (flawed) by device failure, EMI, cautery or defibrillation procedures. Therefore, most implantable pulse generators have a power-on reset (POR) circuit that resets memory when power supply glitches occur. Any stored data is then erased and lost to the follow-up clinician.
Alternative methods proposed for the storage of analog signals in implantable pulse generators include magnetic bubble memories (see Chapter 3, Part 4 "The Third Decade of Cardiac Pacing") and Charge Coupled Devices (CCD). Present problems with bubble memories include the limited size of the memory (or alternatively, the large size of the integrated circuit), the difficulty in the read/write mechanism required and the complexity of the interface circuitry to the rest of the implantable pulse generator circuit (typically constructed of CMOS circuitry). Alternatively, in a CCD, the signal to be recorded is stored as a charge on an integrated capacitor. However analog information cannot be stored on a CCD for very long because the capacitor leakage rate on the CCD is too high to maintain accuracy for any significant length of time.
What is needed is a device that can electrically store analog information in an implantable medical device with reasonable precision, for long terms, with substantially reduced complexity, minimized current drain from the battery, greatly reduced memory requirements, increased telemetry transmission rates and the integration of signals marking specific function of the implanted device simultaneous with the recording of the analog signal. The system of the present invention provides for an efficient electronic recording and playback system for an implantable medical device which stores signal information in considerably less memory, with reduced complexity, and reduced current drain than that required for digital storage, and includes markers indicative of device function.
It is, therefore, an objective of the present invention to provide an apparatus for placing and storing analog data into nonvolatile memory of an implantable medical device.
It is furthermore an objective of the present invention to compress the analog data prior to storage, whereby less memory is required. Adequate fidelity for clinical use is maintained during the compression operation.
It is furthermore an objective of the present invention to provide for the transmission of the analog data to an external peripheral for subsequent clinical use.
It is furthermore an objective of the present invention to incorporate signals indicative of implanted device function interleaved with the stored analog data.
It is furthermore an objective of the present invention to utilize the stored analog data to enable arrhythmia detection and treatment.
It is furthermore an objective of the present invention to utilize the stored analog data to enable the detection of an evoked response in an auto capture mode of operation.
The above and other objectives that will herein after appear, and the nature of the invention, will more clearly be understood by reference to the following description, the amended claims and the accompanying drawings.
The foregoing and other features of the present invention will be best appreciated with reference to the detailed description of a specific embodiment of the invention, which follows, read in conjunction with accompanying drawings wherein:
FIG. 1 is a diagram showing the placement in a patient of a pacemaker in accordance with the present invention;
FIG. 2 is a block diagram of the circuitry of a pacemaker in accordance with one embodiment of the present invention;
FIG. 3 is a flow diagram illustrating a mode of operation of the pacemaker of FIG. 2;
FIG. 4 is a flow diagram further illustrating the mode of operation of the pacemaker of FIG. 2;
FIGS. 5 and 6 are flow diagrams with alternative modes of operation of the pacemaker of FIG. 2;
FIG. 7 is a diagram with an alternative mode of operation of the pacemaker of FIG. 2;
FIG. 8 is a flow diagram further illustrating the mode of operation of the pacemaker of FIG. 7;
FIG. 9 is a diagram illustrating the analog voltage waveform stored in memory of the pacemaker of FIG. 2; and
FIG. 10 is a diagram illustrating the display of an external programmer showing the reconstructed analog waveform of FIG. 9 simultaneous with a marker indicator of device function.
The present invention will now be more fully described with reference to the various Figures of the drawings, FIG. 1 showing generally how a pacemaker 10 in accordance with the present invention may be implanted in a patient 12. A pacemaker lead 14 is electrically coupled to pacemaker 10 and extends into the patient's heart 16 via a vein 18. The distal end of lead 14 includes one or more exposed conductive electrodes for receiving electrical cardiac signals and for delivering electrical pacing stimuli to the patient's heart 16. In accordance with the invention to be hereinafter described, the distal end of pacemaker lead 14 may also incorporate a pressure transducer (not shown in FIG. 1 due to the small scale of that Figure) for producing electrical signals representative of the pressure inside heart 16.
Turning to FIG. 2, a block diagram of pacemaker 10 from FIG. 1 is shown. Although the present invention is described in conjunction with a pacemaker 10 having a microprocessor-based architecture, it will be understood that it could be implemented in any logic based, custom integrated circuit architecture, if desired. It will also be understood that the present invention may be utilized in conjunction with other implantable medical devices, such as cardioverters, defibrillators, neural stimulators, cardiac assist systems, and the like.
In the embodiment shown in FIG. 1, pacemaker 10 includes an activity sensor 20, which may be, for example, a piezoelectric element bonded to the inside of the pacemaker's housing. Sensor 20 provides a sensor output which varies as a function of a measured parameter that relates to the metabolic requirements of patient 12. In addition, pacemaker 10 includes a pressure sensor 22 disposed at the distal end of lead 14, as previously noted, which may be similarly used to ascertain the metabolic requirements and/or cardiac output of patient 12. Pressure sensor 22 may be a piezoelectric element such as is disclosed in U.S. Pat. No. 4,407,296 to Anderson, entitled "Integral Hermetic Implantable Pressure Transducer," or U.S. Pat. No. 4,485,813 to Anderson et al., entitled "Implantable Dynamic Pressure Transducer System," each assigned to the assignee of the present invention and incorporated herein by reference.
Pacemaker 10 is schematically shown in FIG. 2 to be electrically coupled via a pacing lead 14 to a patient's heart 16. Lead 14 includes an intracardiac electrode 24 and pressure sensor 22 located near its distal end and positioned within the right ventricular (RV) chamber of heart 16. Lead 14 can carry either unipolar or bipolar electrodes as is well known in the art. In the presently disclosed embodiment, lead 14 which couples pacemaker 10 to the ventricula endocardium can comprise a steroid-tipped, unipolar lead with an integral pressure transducer of the type described in the aforementioned references. Electrode 24 is coupled via suitable lead conductor 14a through input capacitor 26 to node 28 and to input/output terminals of an input/output circuit 30. Output from first sensor 20 is coupled to input/output circuit 30. Output from pressure sensor 22 is also coupled to input/output circuit 30 via suitable lead conductor 14b.
Input/output circuit 30 contains the analog circuits for interface to the heart 16, activity sensor 20, pressure sensor 22, and antenna 52, as well as for the application of stimulating pulses to heart 16 to control its rate as a function thereof under control of the software-implemented algorithms in a microcomputer circuit 32.
Microcomputer circuit 32 comprises an on-board circuit 34 and an off-board circuit 36. On-board circuit 34 includes a microprocessor 38, a system clock circuit 40, and on-board RAM 42 and ROM 44. Off-board circuit 36 includes an off-board RAM/ROM unit 46. Microcomputer circuit 32 is coupled by data communication bus 48 to a digital controller/timer circuit 50. Microcomputer circuit 32 may be fabricated of custom integrated circuit devices augmented by standard RAM/ROM components. Data communication bus 48 is also coupled to an analog memory integrated circuit 80 which includes a DAC 82, an address decode circuit 84, a sample and hold circuit 86, a high voltage supply and associated switches 88 and EEPROM memory cells 90.
It will be understood that the electrical components represented in FIG. 2 are powered by an appropriate implantable battery power source, not shown, in accordance with common practice in the art.
An antenna 52 is connected to input/output circuit 30 for purposes of uplink/downlink telemetry through RF transmitter/receiver (RF TX/RX) unit 54. Telemetering both analog and digital data between antenna 52 and an external device, such as an external programmer (not shown), is accomplished in the presently disclosed embodiment by means of all data first being digitally encoded and then pulse-position modulated on a damped RF carrier, as substantially described in co-pending U.S. patent application Ser. No. 07/468,407, filed on Jan. 22, 1990, entitled "Improved Telemetry Format," which is assigned to the assignee of the present invention and which is incorporated herein by reference.
A crystal oscillator circuit 56, typically a 32,768-Hz crystal-controlled oscillator, provides main timing clock signals to digital controller/timer circuit 50. A Vref/Bias circuit 58 generates a stable voltage reference and bias currents for the analog circuits of input/output circuit 30. An analog-to-digital converter/multiplexor (ADC/MUX) unit 60 digitizes analog signals and voltages to provide "real-time" telemetry of pressure and intracardiac signals and battery end-of-life (EOL) replacement function. A power-on-reset (POR) circuit 62 functions as a means to reset circuitry and related functions to a default condition upon detection of a low battery condition, which will occur upon initial device power-up or will transiently occur in the presence of electromagnetic interference, for example.
The operating commands for controlling the timing of pacemaker 10 are coupled by bus 48 to digital controller/timer circuit 50 wherein digital timers and counters are employed to establish the overall escape interval of the pacemaker, as well as various refractory, blanking, and other timing windows for controlling the operation of the peripheral components within input/output circuit 30.
Digital controller/timer circuit 50 is coupled to a sense amplifier 64 and an electrogram amplifier 66 for receiving amplified and processed signals picked up from electrode 24 through lead conductor 14a and capacitor 26 representative of the electrical activity of the patient's heart 16. Sense amplifier 64 amplifies sensed electrical cardiac signals and provides this amplified signal to peak sense and threshold measurement circuitry 65, which provides an indication of peak sensed voltages and the measured sense amplifier threshold voltage on multiple conductor signal path 67 to digital controller/timer circuit 50. The amplified sense amplifier signal is also provided to a comparator 69. The electrogram signal developed by EGM amplifier 66 is used in those occasions when the implanted device is being interrogated by an external programmer, not shown, in order to transmit by uplink telemetry a representation of the analog electrogram of the patient's electrical heart activity as described in U.S. Pat. No. 4,556,063, issued to Thompson et al., assigned to the assignee of the present invention and incorporated herein by reference. An output pulse generator 68 provides the pacing stimulus to the patient's heart 16 through coupling capacitor 74 in response to a pacing trigger signal developed by digital controller/timer circuit 50 each time the escape interval times out, or an externally transmitted pacing command has been received, or in response to other stored commands as is well known in the pacing art.
Digital controller/timer circuit 50 is coupled to an activity circuit 70 for receiving, processing, and amplifying signals received from activity sensor 20. Activity circuit 70 produces an activity signal which is representative of the patient's metabolic requirements. Similarly, digital controller/timer circuit 50 is coupled to a pressure circuit 72 for receiving, amplifying and processing sensor output from pressure sensor 22. In the presently disclosed embodiment of the invention, pressure circuit 72 produces an amplified, filtered analog pressure signal which is received by digital controller/timer circuit 50. In conjunction with ADC/MUX 60, digital controller/timer circuit samples and digitizes the pressure signal from pressure circuit 72 to obtain a digital representation of the peak value of intracardiac pressure during each cardiac cycle. This value is provided to microprocessor 34, which maintains a running average over a previous number of cardiac cycles (e.g. sixteen) of the intracardiac pulse pressure.
With continued reference to FIG. 2, input/output circuit 30 further includes sensitivity control circuitry 75 coupled between digital controller/timer circuit 50 and sense amplifier circuit 64. Sensitivity control circuit 75 controls the sense amplifier gain and thus the sensing threshold of sense amplifier 64 as instructed by digital controller/timer circuit 50.
With reference to memory 80 of FIG. 2, digital to analog converter (DAC) 82 converts a digital representation of a signal into an analog signal. Address decode 84 controls the addressing of the row and column of analog memory 90 for both writing and reading data. Sample and hold circuit 86 samples an analog signal at a periodic rate to enable the storage of an analog signal in analog memory 90. High voltage (HV) and switch circuit 88 generates an approximate 20 volt DC voltage and, via the switches, stores a representation of an analog signal in analog memory 90. Analog memory 90 is a standard EEPROM memory utilized in this application to store analog signals.
Turning now to FIG. 3, the preferred embodiment for the compression and storage of an analog signal in the pacemaker of FIG. 2 is shown. The signal to be stored may be one or both of the intracardiac signal from the EGM amplifier 66 of FIG. 2 and/or a signal from a sensor such as the pressure sensor 22 shown in FIG. 2. The EGM amplifier 66 and pressure circuit 72 amplify and filter the appropriate physiologic signal from the patient and provide a voltage level suitable for storing in memory 80. The flow diagram of FIG. 3 is initiated at block 102. The data to be stored is sampled and held at block 104 by sample and hold circuit 86 of FIG. 2. At block 106, the data is stored in a section of analog memory 90 via address decode 84 and high voltage supply (HV) and switch circuit 88, all of FIG. 2. Digital data indicative of device function may also be stored interdispersed among the analog signal as herein described later in association with FIGS. 9 and 10. Analog memory 90 may be of the type incorporated in ISD 1016, a telecommunication monolithic integrated circuit from Information Storage Devices, Inc. A preliminary specification dated March, 1991 is incorporated herein by reference in its entirety. Analog data is continuously stored in a circular buffer (a section of analog memory 90), enabling 30 seconds of pre-event data to be frozen upon an event detection period.
Automatic event detection is tested for in block 108 by microcomputer circuit 32 of FIG. 2 which monitors the intracardiac electrogram for arrhythmias, PVCs or runs of PVCs, as shown in co-pending U.S. patent application Ser. No. 07/881,996, filed on May 1, 1992 entitled "Diagnostic Function Data Storage and Telemetry Out for Rate Responsive Cardiac Pacemaker," and assigned to the assignee of the present invention and incorporated herein by reference in its entirety. Alternatively, patient activation by reed switch closure with a hand-held magnet placed over the implant site may also trigger storage of signals. Upon automatic detection of the event, or patient activation, the analog data is converted to digital data at block 110 by 8 bit ADC 60 of FIG. 2. During the data compression process, the sample and hold 104 and storage in buffer 106 are bypassed and the analog data is compressed in real-time. At block 112, the digital data is compressed as will herein below be described. The compressed data is reconverted to analog voltage levels at block 114 via DAC 82 of FIG. 2. At block 116 the marker data from the microcomputer 32 and the reconverted data from block 114 are stored in analog memory 90 via address decode 84 and high voltage supply (HV) and switch circuit 88, all of FIG. 2. A test for 2 more data values is evaluated at block 118. If `YES`, the flow diagram returns to block 110. If `NO`, the flow diagram moves to block 120 where data temporarily stored in a section of analog memory 90 used as a circular buffer is converted, compressed, reconverted and stored as herein described above. Upon completion of storage of the data temporarily stored in the circular buffer, the flow diagram exits at block 122.
In the present embodiment, five minutes of data may be stored along with the 30 seconds of pre-event data from the circular buffer and the time of occurrence from a system clock from microcomputer circuit 32 of FIG. 2. Nine separate events including pre-event, post-event and time of occurrence of each may be stored in an ISD 1016 (a 128K byte) analog memory 80. More or longer episodes may be stored if larger memory capacity or multiple integrated circuits are available. Memory 80 may operate in a freeze mode whereupon being filled with nine separate events, the data is frozen under command of microcomputer 32 until interrogation and reset by an external programmer, not shown. Alternatively, memory 80 may operate in a circular buffer or over-write mode whereby the most recent nine events will be stored in memory and may be read and reviewed by a clinician upon interrogation by the programmer. In either storage mode, the external programmer may reset and reinitiate the storage function under program commands as is well known in the art. The reading of the stored data from analog memory 90 is under control of microcomputer 32, address decode 84 and high voltage and switch circuit 88 whereby a specific memory bit is addressed and the analog signal is reconstructed sequentially, one bit at a time. This signal is routed through bus 48 to input/output circuit 30 for transmission to an external programmer (not shown) via RF transmit/receive circuit 54 and antenna 52.
It should be apparent that other methods of patient activation may be used such as tapping on the pacemaker can with a signal generated by the activity sensor 20 of FIG. 2 being detected to trigger the recording episode. Additionally, a simple patient programmer may be utilized to trigger the storage event.
Turning now to FIG. 4, a flow diagram is shown which illustrates the compression process 110 of FIG. 3 in accordance with the presently disclosed embodiment of the invention. The flow diagram of FIG. 4 begins with the starting of the compression process at block 200 by event detection 104 of FIG. 3. At block 202 a counter, COMPRESS-- CYCLE, is set to 1. The first voltage value data point (n1) is saved at block 204. The following two data points, n2 and n3, are obtained in block 206 from block 110 of FIG. 3. Data point n2 is compared to the saved data point n1 at block 208. If n2 is equal to, or greater than, n1, block 208 returns a `YES` and the larger of n2 or n3 is saved at block 210. If n2 is smaller than n1, then the smaller of n2 or n3 is saved at block 220. More data is tested for at block 212. If at least 2 more data values are available, the flow diagram returns to block 206. If block 212 returns a `NO`, the COMPRESS-- CYCLE counter is incremented by 1. At block 216, if the COMPRESS-- CYCLE counter is greater than 2 the flow diagram is exited at block 218. If the COMPRESS-- CYCLE counter is less than, or equal to 2 the flow diagram returns to block 204. As described in this preferred embodiment, the flow diagram is serially repeated a second time on the data compressed and stored by the algorithm of FIG. 4 to enable the compression of data by a factor of 4 to 1. The flow diagram of FIG. 4 retains good fidelity by storing the maximum or minimum transition points in a waveform while reducing the stored data by 75%.
Turning now to FIG. 5, a flow diagram is shown which illustrates an alternative embodiment whereby the implantable device 10 of FIG. 1 incorporates an implantable 24 hour holter monitor. The signal to be stored may be one or both, the intracardiac signal from EGM amplifier 66 of FIG. 2 and/or the signal from a sensor such as the pressure sensor 22 shown in FIG. 2. The flow diagram is initiated at block 302 by the methods as herein described above (e.g. event detection, programming or patient activation). The analog signal is converted to a digital word in block 304 via the 8-bit ADC 60 of FIG. 2. At block 306, the data is compressed via the technique as described herein above and shown in FIG. 4. At block 308, the compressed digital data is reconverted to voltage levels via the DAC 82 shown in FIG. 2. At block 310, the marker data from the microcomputer circuit 32 of FIG. 2 and the reconverted data from block 308 are stored in analog memory 90 of FIG. 2. A test for more data is evaluated at block 312. If `YES`, the flow diagram returns to block 304. If `NO`, the flow diagram exits at block 314. Block 310 may store data in a freeze mode or an over-write mode under control of microcomputer 32, FIG. 2.
Referring now to FIG. 6, a flow diagram is shown which illustrates an alternative embodiment whereby the implantable device 10, FIG. 1, incorporates storage of analog EGM data directly without an intervening conversion to digital data and subsequent reconversion to analog data. The signal to be stored may be one or both, the intracardiac signal from EGM amplifier 66 of FIG. 2 and/or the signal from a sensor such as the pressure sensor 22 shown in FIG. 2. The flow diagram is initiated at block 402 by the methods as described herein above (e.g. event detection, programming or patient activation). The analog data is sampled and held at block 404 by a sample and hold circuit 86 of FIG. 2. The sampling may occur at a 128 Hz rate for adequate clinically useful data. At block 406, the data is stored in analog memory 90 via address control 84 and high voltage supply (HV) and switches 88 of FIG. 2. At block 408, a test for more data is entered. If `YES`, the flow diagram returns to sample and hold block 404. If `NO`, the flow diagram is exited at block 410. This embodiment is simpler, requires less circuitry and less current drain from the battery because of the elimination of the analog to digital conversion 304, the compression of data 306 and the digital to analog conversion 308 from FIG. 5. The embodiment shown in FIG. 6 will have improved fidelity and will compress data to 8:1 versus a digital equivalent.
Finally turning to FIG. 7, a block diagram is shown which illustrates an alternative embodiment whereby the implantable device 10, FIG. 1, incorporates the storage and compression of analog data without the conversion of the analog data to digital data and the subsequent reconversion to analog data as described in the embodiment of FIG. 5. The signal to be stored may be one or both, the intracardiac signal from EGM amplifier 66 of FIG. 2 and/or the signal from a sensor such as the pressure sensor 22 shown in FIG. 2. A sample and hold circuit 502, sampled at a 128 Hz rate, generates analog voltage data that is stored temporarily in analog memory cells 506, 508, and 510 under control of MUX control circuit 504.
The first analog voltage value/data is stored in cell 510 and in the first memory location. The next two data samples are stored in cells 506 and 508, respectively. Comparator 512 compares the voltage level of analog cells 506 and 508 indicating, by a true logic level, if the voltage in cell 506 is greater than 508. Alternatively, a false logic level indicates that the voltage in cell 508 is greater than the voltage in cell 506. Similarly, comparator 514 compares the voltage level of analog cells 508 and 510 indicating by a true logic level if the voltage in cell 508 is greater than 510. Alternatively, a false logic level indicates that the voltage in cell 510 is greater than the voltage in cell 508. Microcomputer 32, FIG. 2, determines by a simple process flow, shown in FIG. 8, which value is stored in analog memory 516 by control/MUX circuit 504.
Referring to FIG. 8, a block diagram is shown which illustrates a flow diagram associated with the compression of data from FIG. 7. The flow diagram of FIG. 8 begins by initiating the compression process at block 600 by event detection 104 of FIG. 3. The first data value (C) is stored in temporary cell 510 and the first address in memory in block 602. The next two values of data are stored in cells 508 (B) and 506 (A) respectively by block 624. If comparator 514 is `TRUE` at block 604, the flow diagram tests if comparator 512 (D) is TRUE in block 606. If `TRUE`, the analog value stored in 506 is stored in memory and in cell 510 by block 618. If at block 606, comparator 514 (E) is `FALSE`, the analog value stored in cell 508 is stored in memory and cell 510 by block 618. If at block 604, comparator 514 is `FALSE` and comparator 512 is `TRUE`, the analog value in cell 506 is stored in memory and cell 510 at block 618. If at block 612, comparator 512 is `FALSE`, the analog value stored in cell 508 is stored in memory and cell 510 by block 618. Block 620 tests for 2 more data values; if `YES`, the flow diagram returns to block 624. If `NO`, the compression process exits and stops at block 622.
After the analog signals are stored as herein above described, the analog data is converted to a signal for transmission to an external peripheral, such as a programmer, at a subsequent follow-up either via a clinic or hospital office visit or transtelephonically. Telemetry techniques are well known to those skilled in the art. Specific reference is made to converting the stored analog voltage to a pulse position modulated format as taught in Medtronic U.S. Pat. No. 4,556,063 to Thompson et. al, and incorporated herein by reference. Alternatively, the stored analog voltage may be digitized by an ADC and transmitted via the method taught in copending U.S. patent application Ser. No. 07/468,407 filed on Jan. 22, 1990, entitled "Improved Telemetry Format," which is assigned to the assignee of the present invention and which is incorporated herein by reference. The high data rate telemetry system of the '407 application would be a preferred method for transmitting the stored data to a peripheral allowing data to be stored at a low rate (e.g., 32 samples per second to even one sample per hour or per day) and transmitted to a peripheral at a very high rate.
FIGS. 9 and 10 demonstrate the incorporation of marker or event indication information into the stored data. A marker indication of device function is entered into the stored analog data stream by utilizing a single bit indicator of -VMAX followed by a selectable voltage value indicating a marker of specific device function. In present day embodiments, intracardiac signal data is lost when digital marker information is simultaneously transmitted with the intracardiac signal because signal data bits are removed and replaced with digital data indicative of device function. FIG. 9 shows an example of the stored voltage 700 in the preferred embodiment of FIG. 3. At 702, the marker indicator of -30 mVolts (-VMAX) is indicated. At 704, a value of -10 mVolts indicates a ventricular event. In a preferred embodiment for a dual chamber (DDD) pacemaker, the following are selectable voltage levels for data bit 704:
______________________________________Event Voltage______________________________________.sup.V Sense -10 mV.sup.V Refractory Sense -20 mV.sup.V Pace -30 mV.sup.A Sense +10 mV.sup.A Refractory Sense +20 mV.sup.A Pace +30 mV______________________________________
FIG. 10 shows the reconstructed and displayed EGM signal 802 with a ventricular sense (VSense) marker indicator 800 displayed on an external peripheral/programmer graphics screen or printed or plotted to a paper hardcopy. Note that the marker information has been removed from the analog data signal and the adjacent analog data points reconnected. Similarly, the time of occurrence of each stored event may be encoded and stored as herein described above.
In addition to the storage of analog data and subsequent telemetry to a programmer as taught herein above, a stored arrhythmia episode may be processed by microcomputer 32 to initiate a pacing, cardioversion or defibrillation therapy as is known in the art. Additionally, a stored signal indicative of capture, non-capture or a fusion beat may be compared on a periodic, or a beat-by-beat basis to the signal seen by the sense amplifier 64 after a pacing stimulus from output circuit 68. If an evoked response is not indicated (non-capture), the output stimulus pulse width and/or amplitude may be increased to regain capture as disclosed in U.S. Pat. No. 4,858,610 issued to Callaghan, et al., U.S. Pat. No. 4,878,497 issued to Callaghan, et al., and U.S. Pat. No. 4,729,376 issued to Decote, all of which are incorporated herein by reference in their entireties. The compression function may be performed by microcomputer 32 by pattern matching the periodic signal within a window from 5 to 80 mSec after output stimulus to the stored representation of the signal indicative of capture. Alternatively, the negative magnitude of the stored non-capture signal may be summed with the periodic signal with the resultant signal being indicative of an evoked response, if present.
From the foregoing detailed descriptions of particular embodiments of the invention, it should be apparent that a pacemaker has been disclosed which is provided with the capability of the compression and storing of a significant amount of analog data such as an intracardiac electrogram. While the particular embodiments of the present invention have been described herein in detail, it is to be understood that various alterations, modifications, and substitutions can be made therein without departing from the spirit and scope of the present invention, as defined in the claims, which follow.
|Patente citada||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US4223678 *||3 May 1978||23 Sep 1980||Mieczyslaw Mirowski||Arrhythmia recorder for use with an implantable defibrillator|
|US4295474 *||2 Oct 1979||20 Oct 1981||The Johns Hopkins University||Recorder with patient alarm and service request systems suitable for use with automatic implantable defibrillator|
|US4407288 *||16 Mar 1981||4 Oct 1983||Mieczyslaw Mirowski||Implantable heart stimulator and stimulation method|
|US4407296 *||12 Sep 1980||4 Oct 1983||Medtronic, Inc.||Integral hermetic impantable pressure transducer|
|US4485813 *||19 Nov 1981||4 Dic 1984||Medtronic, Inc.||Implantable dynamic pressure transducer system|
|US4556063 *||7 Dic 1984||3 Dic 1985||Medtronic, Inc.||Telemetry system for a medical device|
|US4625730 *||9 Abr 1985||2 Dic 1986||The Johns Hopkins University||Patient ECG recording control for an automatic implantable defibrillator|
|US4729376 *||28 May 1985||8 Mar 1988||Cordis Corporation||Cardiac pacer and method providing means for periodically determining capture threshold and adjusting pulse output level accordingly|
|US4800883 *||2 Abr 1986||31 Ene 1989||Intermedics, Inc.||Apparatus for generating multiphasic defibrillation pulse waveform|
|US4858610 *||8 Feb 1988||22 Ago 1989||Telectronics, N.V.||Detection of cardiac evoked potentials|
|US4878497 *||25 Mar 1988||7 Nov 1989||Telectronics N.V.||Pacemaker with improved automatic output regulation|
|US5127404 *||25 Sep 1991||7 Jul 1992||Medtronic, Inc.||Telemetry format for implanted medical device|
|1||Edited by Barold et al., "Memory Technology and Implantable Holter Systems", Advances in Technology and Clinical Applications: The Third Decade of Cardiac Pacing, Chapter Three, Part IV, Futura Publishing Company, Mount Kisco, N.Y., 1982.|
|2||*||Edited by Barold et al., Memory Technology and Implantable Holter Systems , Advances in Technology and Clinical Applications: The Third Decade of Cardiac Pacing, Chapter Three, Part IV, Futura Publishing Company, Mount Kisco, N.Y., 1982.|
|3||*||Thomas J. Lynch, Ph.D., Data Compression Techniques and Applications, Van Nostrand Reinhold Company, New York, pp. 256 259.|
|4||Thomas J. Lynch, Ph.D., Data Compression Techniques and Applications, Van Nostrand Reinhold Company, New York, pp. 256-259.|
|Patente citante||Fecha de presentación||Fecha de publicación||Solicitante||Título|
|US5391188 *||17 Jun 1993||21 Feb 1995||Medtronic, Inc.||Low cost implantable medical device|
|US5518001 *||17 Jun 1994||21 May 1996||Pacesetter, Inc.||Cardiac device with patient-triggered storage of physiological sensor data|
|US5693076 *||16 Ene 1996||2 Dic 1997||Medtronic, Inc.||Compressed patient narrative storage in and full text reconstruction from implantable medical devices|
|US5727552 *||11 Ene 1996||17 Mar 1998||Medtronic, Inc.||Catheter and electrical lead location system|
|US5732708 *||9 Ago 1996||31 Mar 1998||Pacesetter, Inc.||Method for storing EGM and diagnostic data in a read/write memory of an implantable cardiac therapy device|
|US5785660 *||28 Mar 1996||28 Jul 1998||Pacesetter, Inc.||Methods and apparatus for storing intracardiac electrograms|
|US5819740 *||18 Dic 1996||13 Oct 1998||Medtronic, Inc.||System and method for compressing digitized signals in implantable and battery powered devices|
|US5836889 *||3 Mar 1997||17 Nov 1998||Biotronik Mess- Und Therapiegeraete Gmbh & Co. Ingenieurbuero Berlin||Method and apparatus for storing signals in an implantable medical device|
|US5836982 *||19 Feb 1997||17 Nov 1998||Medtronic, Inc.||System and method of data compression and non-linear sampling for implantable and battery-powered devices|
|US5861013 *||29 Abr 1997||19 Ene 1999||Medtronic Inc.||Peak tracking capture detection circuit and method|
|US5871512 *||9 Abr 1998||16 Feb 1999||Medtronic, Inc.||Microprocessor capture detection circuit and method|
|US5873898 *||29 Abr 1997||23 Feb 1999||Medtronic, Inc.||Microprocessor capture detection circuit and method|
|US5944745 *||25 Sep 1996||31 Ago 1999||Medtronic, Inc.||Implantable medical device capable of prioritizing diagnostic data and allocating memory for same|
|US5954756 *||9 Abr 1998||21 Sep 1999||Medtronic, Inc.||Microprocessor capture detection circuit and method|
|US6038474 *||2 Mar 1999||14 Mar 2000||Cardiac Pacemakers, Inc.||Pseudo-fusion management during automatic capture verification|
|US6068651 *||26 Mar 1998||30 May 2000||Pacesetter, Inc.||Atrial defibrillation lock out feature|
|US6102874 *||19 Ene 2000||15 Ago 2000||Medtronic, Inc.||Implantable medical device for tracking patient functional status|
|US6134473 *||14 Abr 1999||17 Oct 2000||Medtronic, Inc.||Microprocessor capture detection circuit and method|
|US6144881 *||18 Sep 1998||7 Nov 2000||Medtronic, Inc.||Capture detection circuit for pulses and physiologic signals|
|US6190324||28 Abr 1999||20 Feb 2001||Medtronic, Inc.||Implantable medical device for tracking patient cardiac status|
|US6200265||16 Abr 1999||13 Mar 2001||Medtronic, Inc.||Peripheral memory patch and access method for use with an implantable medical device|
|US6230059||17 Mar 1999||8 May 2001||Medtronic, Inc.||Implantable monitor|
|US6275731||29 Dic 1999||14 Ago 2001||Cardiac Pacemakers, Inc.||Pseudo-fusion management during automatic capture verification|
|US6280409||28 Sep 1999||28 Ago 2001||Medtronic, Inc.||Medical for tracking patient functional status|
|US6317626||3 Nov 1999||13 Nov 2001||Medtronic, Inc.||Method and apparatus for monitoring heart rate|
|US6385485 *||20 Dic 1999||7 May 2002||Ela Medical S.A.||Continuously monitoring cardiac events in an active implantable medical device|
|US6438407||20 Mar 2000||20 Ago 2002||Medtronic, Inc.||Method and apparatus for monitoring physiologic parameters conjunction with a treatment|
|US6473649||22 Dic 1999||29 Oct 2002||Cardiac Pacemakers, Inc.||Rate management during automatic capture verification|
|US6508771||1 Dic 1999||21 Ene 2003||Medtronic, Inc.||Method and apparatus for monitoring heart rate|
|US6564807 *||30 Sep 2000||20 May 2003||Alfred E. Mann Foundation For Scientific Research||System of implantable devices for monitoring and/or affecting body parameters|
|US6582365 *||9 Jul 1999||24 Jun 2003||The United States Of America As Represented By The Administrator Of The National Aeronautics And Space Administration||Advanced sensor systems for biotelemetry|
|US6599242||19 Jul 2000||29 Jul 2003||Medtronic, Inc.||Method and apparatus for data compression of heart signals|
|US6649078||6 Dic 2000||18 Nov 2003||The Regents Of The University Of California||Thin film capillary process and apparatus|
|US6690959||31 Ago 2001||10 Feb 2004||Medtronic, Inc.||Skin-mounted electrodes with nano spikes|
|US6714811||1 Dic 1999||30 Mar 2004||Medtronic, Inc.||Method and apparatus for monitoring heart rate|
|US6719689 *||30 Abr 2001||13 Abr 2004||Medtronic, Inc.||Method and system for compressing and storing data in a medical device having limited storage|
|US6760615||31 Oct 2001||6 Jul 2004||Medtronic, Inc.||Method and apparatus for discriminating between tachyarrhythmias|
|US6766190||31 Oct 2001||20 Jul 2004||Medtronic, Inc.||Method and apparatus for developing a vectorcardiograph in an implantable medical device|
|US6910084||30 Abr 2001||21 Jun 2005||Medtronic, Inc||Method and system for transferring and storing data in a medical device with limited storage and memory|
|US6922584||28 Nov 2001||26 Jul 2005||Medtronic, Inc.||Method and apparatus for discrimination atrial fibrillation using ventricular rate detection|
|US7027858||11 Sep 2002||11 Abr 2006||Medtronic, Inc.||Methods and apparatus for cardiac R-wave sensing in a subcutaneous ECG waveform|
|US7031765||11 Nov 2002||18 Abr 2006||Medtronic, Inc||Algorithms for detecting atrial arrhythmias from discriminatory signatures of ventricular cycle lengths|
|US7114502||21 Nov 2003||3 Oct 2006||Alfred E. Mann Foundation For Scientific Research||Battery-powered patient implantable device|
|US7167755||5 Oct 2004||23 Ene 2007||Cardiac Pacemakers, Inc.||Adaptive software configuration for a medical device|
|US7286872||7 Oct 2003||23 Oct 2007||Cardiac Pacemakers, Inc.||Method and apparatus for managing data from multiple sensing channels|
|US7288066||1 Nov 2004||30 Oct 2007||Medtronic, Inc.||Data compression method for implantable medical devices|
|US7294108||27 Ene 2005||13 Nov 2007||Pacesetter, Inc.||Cardiac event microrecorder and method for implanting same|
|US7359837||27 Abr 2006||15 Abr 2008||Medtronic, Inc.||Peak data retention of signal data in an implantable medical device|
|US7450998||21 Nov 2003||11 Nov 2008||Alfred E. Mann Foundation For Scientific Research||Method of placing an implantable device proximate to neural/muscular tissue|
|US7471980 *||22 Dic 2003||30 Dic 2008||Cardiac Pacemakers, Inc.||Synchronizing continuous signals and discrete events for an implantable medical device|
|US7513257||21 Jul 2005||7 Abr 2009||Alfred E. Mann Foundation For Scientific Research||System of implantable devices for monitoring and/or affecting body parameters|
|US7587237||2 Feb 2004||8 Sep 2009||Cardionet, Inc.||Biological signal management|
|US7610083||27 Abr 2006||27 Oct 2009||Medtronic, Inc.||Method and system for loop recording with overlapping events|
|US7621905||12 Ago 2003||24 Nov 2009||Remon Medical Technologies Ltd.||Devices for intrabody delivery of molecules and systems and methods utilizing same|
|US7630773||16 Nov 2006||8 Dic 2009||Cardiac Pacemakers, Inc.||Adaptive software configuration for a medical device|
|US7641619||19 Sep 2007||5 Ene 2010||Remon Medical Technologies, Ltd.||Barometric pressure correction based on remote sources of information|
|US7724148 *||20 Nov 2006||25 May 2010||Radi Medical Systems Ab||Transceiver unit in a pressure measurement system|
|US7756573||5 Sep 2006||13 Jul 2010||Cardiac Pacemakers, Inc.||Implantable medical device diagnostic data acquisition and storage|
|US7764988||27 Abr 2006||27 Jul 2010||Medtronic, Inc.||Flexible memory management scheme for loop recording in an implantable device|
|US7765088||26 Feb 2008||27 Jul 2010||Medtronic, Inc.||Peak data retention of signal data in an implantable medical device|
|US7813808||23 Nov 2005||12 Oct 2010||Remon Medical Technologies Ltd||Implanted sensor system with optimized operational and sensing parameters|
|US7853322||28 Abr 2006||14 Dic 2010||Medtronic, Inc.||Closed-loop therapy adjustment|
|US7917199||26 Abr 2006||29 Mar 2011||Medtronic, Inc.||Patient event marking in combination with physiological signals|
|US7948148||13 Oct 2009||24 May 2011||Remon Medical Technologies Ltd.||Piezoelectric transducer|
|US7955268||20 Jul 2007||7 Jun 2011||Cardiac Pacemakers, Inc.||Multiple sensor deployment|
|US7957797||1 Dic 2006||7 Jun 2011||Medtronic, Inc.||Closed-loop therapy adjustment|
|US7957809||1 Dic 2006||7 Jun 2011||Medtronic, Inc.||Closed-loop therapy adjustment|
|US8024029||2 Nov 2005||20 Sep 2011||Medtronic, Inc.||Techniques for user-activated data retention in an implantable medical device|
|US8108033||2 Nov 2005||31 Ene 2012||Medtronic, Inc.||Techniques for data retention upon detection of an event in an implantable medical device|
|US8115635||24 Nov 2009||14 Feb 2012||Abbott Diabetes Care Inc.||RF tag on test strips, test strip vials and boxes|
|US8150531||30 Abr 2009||3 Abr 2012||Medtronic, Inc.||Associating therapy adjustments with patient posture states|
|US8174395||30 Abr 2010||8 May 2012||St. Jude Medical Systems Ab||Transceiver unit in a measurement system|
|US8175720||30 Abr 2009||8 May 2012||Medtronic, Inc.||Posture-responsive therapy control based on patient input|
|US8200324||1 Jun 2010||12 Jun 2012||Cardiac Pacemakers, Inc.||Implantable medical device diagnostic data acquisition and storage|
|US8200340||30 Abr 2009||12 Jun 2012||Medtronic, Inc.||Guided programming for posture-state responsive therapy|
|US8209028||30 Abr 2009||26 Jun 2012||Medtronic, Inc.||Objectification of posture state-responsive therapy based on patient therapy adjustments|
|US8219206||30 Abr 2009||10 Jul 2012||Medtronic, Inc.||Dwell time adjustments for posture state-responsive therapy|
|US8223021||24 Nov 2009||17 Jul 2012||Abbott Diabetes Care Inc.||RF tag on test strips, test strip vials and boxes|
|US8224431||2 Nov 2005||17 Jul 2012||Medtronic, Inc.||Techniques for selective channel processing and data retention in an implantable medical device|
|US8231555||30 Abr 2009||31 Jul 2012||Medtronic, Inc.||Therapy system including multiple posture sensors|
|US8231556||30 Abr 2009||31 Jul 2012||Medtronic, Inc.||Obtaining baseline patient information|
|US8249718||30 Abr 2009||21 Ago 2012||Medtronic, Inc.||Programming posture state-responsive therapy with nominal therapy parameters|
|US8271093||17 Sep 2004||18 Sep 2012||Cardiac Pacemakers, Inc.||Systems and methods for deriving relative physiologic measurements using a backend computing system|
|US8280517||26 Ago 2009||2 Oct 2012||Medtronic, Inc.||Automatic validation techniques for validating operation of medical devices|
|US8282580||30 Abr 2009||9 Oct 2012||Medtronic, Inc.||Data rejection for posture state analysis|
|US8315710||30 Abr 2009||20 Nov 2012||Medtronic, Inc.||Associating therapy adjustments with patient posture states|
|US8323218||30 Abr 2009||4 Dic 2012||Medtronic, Inc.||Generation of proportional posture information over multiple time intervals|
|US8326420||30 Abr 2009||4 Dic 2012||Medtronic, Inc.||Associating therapy adjustments with posture states using stability timers|
|US8332041||30 Abr 2009||11 Dic 2012||Medtronic, Inc.||Patient interaction with posture-responsive therapy|
|US8358210||24 Nov 2009||22 Ene 2013||Abbott Diabetes Care Inc.||RF tag on test strips, test strip vials and boxes|
|US8388555||28 Abr 2010||5 Mar 2013||Medtronic, Inc.||Posture state classification for a medical device|
|US8390455||24 Nov 2009||5 Mar 2013||Abbott Diabetes Care Inc.||RF tag on test strips, test strip vials and boxes|
|US8396565||23 Oct 2003||12 Mar 2013||Medtronic, Inc.||Automatic therapy adjustments|
|US8401666||30 Abr 2009||19 Mar 2013||Medtronic, Inc.||Modification profiles for posture-responsive therapy|
|US8410940||11 Abr 2012||2 Abr 2013||St. Jude Medical Systems Ab||Transceiver unit in a measurement system|
|US8437861||30 Abr 2009||7 May 2013||Medtronic, Inc.||Posture state redefinition based on posture data and therapy adjustments|
|US8447411||30 Abr 2009||21 May 2013||Medtronic, Inc.||Patient interaction with posture-responsive therapy|
|US8461997||30 Abr 2010||11 Jun 2013||St. Jude Medical Systems Ab||Transceiver unit in a measurement system|
|US8478417||2 Nov 2005||2 Jul 2013||Medtronic, Inc.||Techniques for data reporting in an implantable medical device|
|US8504150||23 Mar 2012||6 Ago 2013||Medtronic, Inc.||Associating therapy adjustments with posture states using a stability timer|
|US8515549||30 Abr 2009||20 Ago 2013||Medtronic, Inc.||Associating therapy adjustments with intended patient posture states|
|US8515550||30 Abr 2009||20 Ago 2013||Medtronic, Inc.||Assignment of therapy parameter to multiple posture states|
|US8542122||17 Ene 2013||24 Sep 2013||Abbott Diabetes Care Inc.||Glucose measurement device and methods using RFID|
|US8579834||6 Ene 2011||12 Nov 2013||Medtronic, Inc.||Display of detected patient posture state|
|US8583252||30 Abr 2009||12 Nov 2013||Medtronic, Inc.||Patient interaction with posture-responsive therapy|
|US8644945||30 Abr 2009||4 Feb 2014||Medtronic, Inc.||Patient interaction with posture-responsive therapy|
|US8649860||17 May 2010||11 Feb 2014||Cardiac Pacemakers, Inc.||Adaptive event storage in implantable device|
|US8688225||30 Abr 2009||1 Abr 2014||Medtronic, Inc.||Posture state detection using selectable system control parameters|
|US8698638||19 Mar 2013||15 Abr 2014||St. Jude Medical Systems Ab||Transceiver unit in a measurement system|
|US8704688||20 Mar 2012||22 Abr 2014||Cardiac Pacemakers, Inc.||Implantable medical device diagnostic data acquisition and storage|
|US8708934||30 Abr 2009||29 Abr 2014||Medtronic, Inc.||Reorientation of patient posture states for posture-responsive therapy|
|US8731656||6 Jun 2011||20 May 2014||Medtronic, Inc.||Closed-loop therapy adjustment|
|US8751011||30 Abr 2009||10 Jun 2014||Medtronic, Inc.||Defining therapy parameter values for posture states|
|US8755901||30 Abr 2009||17 Jun 2014||Medtronic, Inc.||Patient assignment of therapy parameter to posture state|
|US8757485||5 Sep 2012||24 Jun 2014||Greatbatch Ltd.||System and method for using clinician programmer and clinician programming data for inventory and manufacturing prediction and control|
|US8758274||28 Abr 2010||24 Jun 2014||Medtronic, Inc.||Automated adjustment of posture state definitions for a medical device|
|US8761897||30 Ago 2013||24 Jun 2014||Greatbatch Ltd.||Method and system of graphical representation of lead connector block and implantable pulse generators on a clinician programmer|
|US8768446||26 Abr 2006||1 Jul 2014||Medtronic, Inc.||Clustering with combined physiological signals|
|US8812125||31 Ago 2012||19 Ago 2014||Greatbatch Ltd.||Systems and methods for the identification and association of medical devices|
|US8838217 *||10 Nov 2009||16 Sep 2014||Makor Issues And Rights Ltd.||System and apparatus for providing diagnosis and personalized abnormalities alerts and for providing adaptive responses in clinical trials|
|US8862229||3 Jun 2010||14 Oct 2014||Cardiac Pacemakers, Inc.||System and method for monitoring cardiovascular pressure|
|US8868199||22 Ago 2013||21 Oct 2014||Greatbatch Ltd.||System and method of compressing medical maps for pulse generator or database storage|
|US8886302||30 Abr 2009||11 Nov 2014||Medtronic, Inc.||Adjustment of posture-responsive therapy|
|US8903486||13 Dic 2010||2 Dic 2014||Medtronic, Inc.||Closed-loop therapy adjustment|
|US8903496||31 Ago 2012||2 Dic 2014||Greatbatch Ltd.||Clinician programming system and method|
|US8905948||31 Oct 2012||9 Dic 2014||Medtronic, Inc.||Generation of proportional posture information over multiple time intervals|
|US8958885||30 Abr 2009||17 Feb 2015||Medtronic, Inc.||Posture state classification for a medical device|
|US8983616||5 Sep 2012||17 Mar 2015||Greatbatch Ltd.||Method and system for associating patient records with pulse generators|
|US9026223||30 Abr 2009||5 May 2015||Medtronic, Inc.||Therapy system including multiple posture sensors|
|US9050471||30 Abr 2009||9 Jun 2015||Medtronic, Inc.||Posture state display on medical device user interface|
|US9131843||10 Abr 2014||15 Sep 2015||Makor Issues and Rights, Ltd.||System and apparatus for providing diagnosis and personalized abnormalities alerts and for providing adaptive responses in clinical trials|
|US9149210||28 Abr 2010||6 Oct 2015||Medtronic, Inc.||Automated calibration of posture state classification for a medical device|
|US9174055||11 Nov 2013||3 Nov 2015||Medtronic, Inc.||Display of detected patient posture state|
|US9180302||27 Ago 2013||10 Nov 2015||Greatbatch Ltd.||Touch screen finger position indicator for a spinal cord stimulation programming device|
|US9220461||18 Mar 2014||29 Dic 2015||St. Jude Medical Coordination Center Bvba||Transceiver unit in a measurement system|
|US9259177||5 Ago 2014||16 Feb 2016||Medtronic, Inc.||Techniques for data retention upon detection of an event in an implantable medical device|
|US9259577||22 Ago 2013||16 Feb 2016||Greatbatch Ltd.||Method and system of quick neurostimulation electrode configuration and positioning|
|US9272091||29 Abr 2015||1 Mar 2016||Medtronic, Inc.||Posture state display on medical device user interface|
|US9314640||29 Oct 2015||19 Abr 2016||Greatbatch Ltd.||Touch screen finger position indicator for a spinal cord stimulation programming device|
|US9327070||30 Abr 2009||3 May 2016||Medtronic, Inc.||Medical device therapy based on posture and timing|
|US9327129||30 Abr 2009||3 May 2016||Medtronic, Inc.||Blended posture state classification and therapy delivery|
|US9339658||5 Feb 2014||17 May 2016||Cardiac Pacemakers, Inc.||Adaptive event storage in implantable device|
|US9357949||5 Ene 2011||7 Jun 2016||Medtronic, Inc.||User interface that displays medical therapy and posture data|
|US9375582||31 Ago 2012||28 Jun 2016||Nuvectra Corporation||Touch screen safety controls for clinician programmer|
|US9440084||30 Abr 2009||13 Sep 2016||Medtronic, Inc.||Programming posture responsive therapy|
|US9471753||31 Ago 2012||18 Oct 2016||Nuvectra Corporation||Programming and virtual reality representation of stimulation parameter Groups|
|US9507912||30 Ago 2013||29 Nov 2016||Nuvectra Corporation||Method and system of simulating a pulse generator on a clinician programmer|
|US9545518||30 Abr 2009||17 Ene 2017||Medtronic, Inc.||Posture state classification for a medical device|
|US9555255||6 Abr 2016||31 Ene 2017||Nuvectra Corporation||Touch screen finger position indicator for a spinal cord stimulation programming device|
|US9560990||9 Jul 2012||7 Feb 2017||Medtronic, Inc.||Obtaining baseline patient information|
|US9566441||30 Abr 2010||14 Feb 2017||Medtronic, Inc.||Detecting posture sensor signal shift or drift in medical devices|
|US9585566||24 Nov 2015||7 Mar 2017||St. Jude Medical Coordination Center Bvba||Transceiver unit in a measurement system|
|US9592387||30 Abr 2009||14 Mar 2017||Medtronic, Inc.||Patient-defined posture states for posture responsive therapy|
|US9594877||31 Ago 2012||14 Mar 2017||Nuvectra Corporation||Virtual reality representation of medical devices|
|US9615788||22 Ago 2013||11 Abr 2017||Nuvectra Corporation||Method and system of producing 2D representations of 3D pain and stimulation maps and implant models on a clinician programmer|
|US9662045||30 Abr 2009||30 May 2017||Medtronic, Inc.||Generation of sleep quality information based on posture state data|
|US9662504||2 May 2016||30 May 2017||Cardiac Pacemakers, Inc.||Adaptive event storage in a medical device|
|US9737719||26 Abr 2012||22 Ago 2017||Medtronic, Inc.||Adjustment of therapy based on acceleration|
|US9767255||27 Ago 2013||19 Sep 2017||Nuvectra Corporation||Predefined input for clinician programmer data entry|
|US9775534||29 May 2013||3 Oct 2017||Braemar Manufacturing, Llc||Biological signal management|
|US9776007||7 Ene 2016||3 Oct 2017||Nuvectra Corporation||Method and system of quick neurostimulation electrode configuration and positioning|
|US9776008||30 Abr 2009||3 Oct 2017||Medtronic, Inc.||Posture state responsive therapy delivery using dwell times|
|US20020188773 *||30 Abr 2001||12 Dic 2002||Frederik Augustijn||Method and system for transferring and storing data in a medical device with limited storage and memory|
|US20040011366 *||17 Mar 2003||22 Ene 2004||Schulman Joseph H.||System of implantable devices for monitoring and/or affecting body parameters|
|US20040103906 *||21 Nov 2003||3 Jun 2004||Schulman Joseph H.||Battery-powered patient implantable device|
|US20050049647 *||29 Ago 2003||3 Mar 2005||Olson Walter H.||Subcutaneous switch for implantable medical device|
|US20050137627 *||22 Dic 2003||23 Jun 2005||Koshiol Allan T.||Synchronizing continuous signals and discrete events for an implantable medical device|
|US20050171448 *||2 Feb 2004||4 Ago 2005||Lev Korzinov||Biological signal management|
|US20050245794 *||29 Abr 2004||3 Nov 2005||Medtronic, Inc.||Communication with implantable monitoring probe|
|US20050256551 *||21 Jul 2005||17 Nov 2005||Alfred E Mann Foundation For Scientific Research||System of implantable devices for monitoring and/or affecting body parameters|
|US20060094968 *||1 Nov 2004||4 May 2006||Drew Touby A||Data compression method for implantable medical devices|
|US20060094970 *||2 Nov 2005||4 May 2006||Medtronic, Inc.||Techniques for selective channel processing and data retention in an implantable medical device|
|US20060094971 *||2 Nov 2005||4 May 2006||Medtronic, Inc.||Techniques for data retention upon detection of an event in an implantable medical device|
|US20060094972 *||2 Nov 2005||4 May 2006||Medtronic, Inc.||Techniques for user-activated data retention in an implantable medical device|
|US20060095091 *||2 Nov 2005||4 May 2006||Medtronic, Inc.||Apparatus for data retention in an implantable medical device|
|US20060095092 *||2 Nov 2005||4 May 2006||Medtronic, Inc.||Techniques for data reporting in an implantable medical device|
|US20060195039 *||26 Abr 2006||31 Ago 2006||Medtronic, Inc.||Clustering with combined physiological signals|
|US20060235489 *||26 Abr 2006||19 Oct 2006||Medtronic, Inc.||Patient event marking in combination with physiological signals|
|US20060287691 *||2 Nov 2005||21 Dic 2006||Medtronic, Inc.||Methods for data retention in an implantable medical device|
|US20070129774 *||28 Abr 2006||7 Jun 2007||Medtronic, Inc.||Closed-loop therapy adjustment|
|US20070150026 *||1 Dic 2006||28 Jun 2007||Medtronic, Inc.||Closed-loop therapy adjustment|
|US20070150029 *||1 Dic 2006||28 Jun 2007||Medtronic, Inc.||Closed-loop therapy adjustment|
|US20070255155 *||27 Abr 2006||1 Nov 2007||Medtronic, Inc.||Method and system for loop recording with overlapping events|
|US20070255531 *||27 Abr 2006||1 Nov 2007||Medtronic, Inc.||Peak data retention of signal data in an implantable medical device|
|US20070293776 *||20 Ago 2007||20 Dic 2007||Cardionet, Inc.||Biological signal management|
|US20080058651 *||5 Sep 2006||6 Mar 2008||Cardiac Pacemakers, Inc.||Implantable Medical Device Diagnostic Data Acquisition and Storage|
|US20080119758 *||20 Nov 2006||22 May 2008||Radi Medical Systems Ab||Transceiver unit in a pressure measurement system|
|US20080235469 *||26 Feb 2008||25 Sep 2008||Medtronic, Inc.||Peak Data Retention of Signal Data In An Implantable Medical Device|
|US20090228073 *||7 Mar 2008||10 Sep 2009||Patrick Scholten||Implantable medical device with patient input mechanism|
|US20100010389 *||30 Abr 2009||14 Ene 2010||Medtronic, Inc.||Generation of proportional posture information over multiple time intervals|
|US20100010390 *||30 Abr 2009||14 Ene 2010||Medtronic, Inc.||Dwell time adjustments for posture state-responsive therapy|
|US20100010575 *||30 Abr 2009||14 Ene 2010||Medtronic, Inc.||Patient interaction with posture-responsive therapy|
|US20100010578 *||30 Abr 2009||14 Ene 2010||Medtronic, Inc.||Patient assignment of therapy parameter to posture state|
|US20100121415 *||30 Abr 2009||13 May 2010||Medtronic, Inc.||Patient interaction with posture-responsive therapy|
|US20100280330 *||30 Abr 2010||4 Nov 2010||St. Jude Medical Systems Ab||Transceiver unit in a measurement system|
|US20100286536 *||30 Abr 2010||11 Nov 2010||St. Jude Medical Systems Ab||Transceiver unit in a measurement system|
|US20100312301 *||3 Jun 2010||9 Dic 2010||Cardiac Pacemakers, Inc.||System and method for monitoring cardiovascular pressure|
|US20110112416 *||10 Nov 2009||12 May 2011||Makor Issues And Rights Ltd.||System and apparatus for providing diagnosis and personalized abnormalities alerts and for providing adaptive responses in clinical trials|
|US20110166471 *||17 Mar 2011||7 Jul 2011||Medtronic, Inc.||Patient Event Marking in Combination with Physiological Signals|
|US20110238130 *||6 Jun 2011||29 Sep 2011||Medtronic, Inc.||Closed-loop therapy adjustment|
|US20110238136 *||6 Jun 2011||29 Sep 2011||Medtronic, Inc.||Closed-loop therapy adjustment|
|USRE38712 *||15 Nov 2002||22 Mar 2005||Biotronik Mess- Und Therapiegeraete Gmbh & Co.||Method and apparatus for storing signals in an implantable medical device|
|DE19609411A1 *||4 Mar 1996||11 Sep 1997||Biotronik Mess & Therapieg||Verfahren und Vorrichtung zur Speicherung von Signalen in einem implantierbaren medizinischen Gerät|
|DE19609411C2 *||4 Mar 1996||25 Nov 1999||Biotronik Mess & Therapieg||Verfahren und Vorrichtung zur Speicherung von Signalen in einem implantierbaren medizinischen Gerät|
|EP0793980A2 *||4 Mar 1997||10 Sep 1997||BIOTRONIK Mess- und Therapiegeräte GmbH & Co Ingenieurbüro Berlin||Signal storage device in an implantable medical apparatus|
|EP0793980A3 *||4 Mar 1997||21 Abr 1999||BIOTRONIK Mess- und Therapiegeräte GmbH & Co Ingenieurbüro Berlin||Signal storage device in an implantable medical apparatus|
|WO1999058056A1||11 May 1999||18 Nov 1999||Medtronic, Inc.||Implantable medical device for tracking patient functional status|
|WO2000051680A1||1 Mar 2000||8 Sep 2000||Medtronic, Inc.||Method and apparatus for monitoring heart rate|
|WO2001070331A2||2 Mar 2001||27 Sep 2001||Medtronic, Inc.||Method and apparatus for monitoring physiologic parameters in conjunction with a treatment regimen|
|WO2002056961A2||28 Nov 2001||25 Jul 2002||Medtronic, Inc.||Method and apparatus for discrimination of atrial fibrillation using ventricular rate detection|
|WO2015077568A1||21 Nov 2014||28 May 2015||Medtronic, Inc.||Method and apparatus for accurately determining heart rate variability and sympathetic reserve|
|Clasificación de EE.UU.||607/9, 607/14, 607/30|
|Clasificación internacional||A61N1/365, A61N1/37, A61B5/00|
|Clasificación cooperativa||A61B5/7232, A61B5/0006, A61N1/3702|
|Clasificación europea||A61B5/00B3B, A61N1/37B|
|26 Ago 1992||AS||Assignment|
Owner name: MEDTRONIC, INC., A CORP. OF MINNESOTA, MINNESOTA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNORS:HOLSCHBACH, JEAN M.;NICHOLS, LUCY M.;THOMPSON, DAVID L.;REEL/FRAME:006256/0952
Effective date: 19920825
|29 Sep 1997||FPAY||Fee payment|
Year of fee payment: 4
|28 Sep 2001||FPAY||Fee payment|
Year of fee payment: 8
|27 Sep 2005||FPAY||Fee payment|
Year of fee payment: 12